Dust Eroded Blade

The purpose is to share. It should be a group portrait, the protagonist has no system, etc. There are rebirthers and reincarnations. No love element. It tells the story of the protagonists who, after their group disintegrated, each prepared for the Demon King's awakening five years later. Five years later, he and the world's top adventurers killed the Demon King, and discovered that there was a big monster behind the scenes. After struggling to kill the big monster, everyone continued to live, and the younger generations gradually forgot about the ancient powerful men, but grew up under their creations.